From: Santosh Shilimkar <santosh.shilimkar@ti.com>
To: akpm@linux-foundation.org, greg@kroah.com
Cc: Aneesh V <aneesh@ti.com>,
linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 0/8] Add TI EMIF SDRAM controller driver
Date: Thu, 16 Feb 2012 16:21:11 +0530 [thread overview]
Message-ID: <4F3CDF9F.9080204@ti.com> (raw)
In-Reply-To: <1328357771-31644-1-git-send-email-aneesh@ti.com>
Andrew, Greg,
On Saturday 04 February 2012 05:46 PM, Aneesh V wrote:
> Add a driver for the EMIF SDRAM controller used in TI SoCs
>
> EMIF is an SDRAM controller that supports, based on its revision,
> one or more of LPDDR2/DDR2/DDR3 protocols.This driver adds support
> for LPDDR2.
>
> The driver supports the following features:
> - Calculates the DDR AC timing parameters to be set in EMIF
> registers using data from the device data-sheets and based
> on the DDR frequency. If data from data-sheets is not available
> default timing values from the JEDEC spec are used. These
> will be safe, but not necessarily optimal
> - API for changing timings during DVFS or at boot-up
> - Temperature alert configuration and handling of temperature
> alerts, if any for LPDDR2 devices
> * temperature alert is based on periodic polling of MR4 mode
> register in DDR devices automatically performed by hardware
> * timings are de-rated and brought back to nominal when
> temperature raises and falls respectively
> - Cache of calculated register values to avoid re-calculating
> them
>
> The driver will need some minor updates when it is eventually
> integrated with DVFS. This can not be done now as DVFS support
> is not available yet in mainline.
>
> Discussions with Santosh Shilimkar <santosh.shilimkar@ti.com>
> were immensely helpful in shaping up the interfaces. Vibhore Vardhan
> <vvardhan@gmail.com> did the initial code snippet for thermal
> handling.
>
> Testing:
> - The driver is tested on OMAP4430 SDP.
> - The driver in a slightly adapted form is also tested on OMAP5.
> - Since mainline kernel doesn't have DVFS support yet,
> testing was done using a test module.
> - Temperature alert handling was tested with simulated interrupts
> and faked temperature values as testing all cases in real-life
> scenarios is difficult.
>
[...]
> arch/arm/mach-omap2/omap_hwmod_44xx_data.c | 110 ++
> drivers/misc/Kconfig | 20 +
> drivers/misc/Makefile | 2 +
> drivers/misc/emif.c | 1522 ++++++++++++++++++++++++++++
> drivers/misc/emif_regs.h | 461 +++++++++
> drivers/misc/jedec_ddr_data.c | 141 +++
> include/linux/emif.h | 257 +++++
> include/linux/jedec_ddr.h | 174 ++++
Any suggestion on where this driver can reside. It's a memory
controller driver which supports standard DDR functionality
as per JDEC specs including thermal alert. On top of
that it does support DVFS using the TI PRCM IP block.
Regards,
Santosh
next prev parent reply other threads:[~2012-02-16 10:51 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-04 12:16 [RFC PATCH 0/8] Add TI EMIF SDRAM controller driver Aneesh V
2012-02-04 12:16 ` [RFC PATCH 1/8] OMAP4: hwmod: add EMIF hw mod data Aneesh V
2012-02-16 10:02 ` Santosh Shilimkar
2012-02-16 10:27 ` Aneesh V
2012-02-04 12:16 ` [RFC PATCH 2/8] misc: ddr: add LPDDR2 data from JESD209-2 Aneesh V
2012-02-16 10:06 ` Santosh Shilimkar
2012-02-16 10:07 ` Santosh Shilimkar
2012-02-16 10:27 ` Aneesh V
2012-02-16 11:10 ` Alan Cox
2012-02-16 11:25 ` Shilimkar, Santosh
2012-02-16 11:55 ` Aneesh V
2012-02-04 12:16 ` [RFC PATCH 3/8] misc: emif: add register definitions for EMIF Aneesh V
2012-02-16 10:10 ` Santosh Shilimkar
2012-02-16 10:30 ` Aneesh V
2012-02-04 12:16 ` [RFC PATCH 4/8] misc: emif: add basic infrastructure for EMIF driver Aneesh V
2012-02-16 10:33 ` Santosh Shilimkar
2012-02-16 11:15 ` Aneesh V
2012-02-16 16:30 ` Cousson, Benoit
2012-02-17 13:26 ` Aneesh V
2012-02-17 13:44 ` Cousson, Benoit
2012-02-17 15:27 ` Aneesh V
2012-02-24 11:10 ` Aneesh V
2012-02-24 11:16 ` Cousson, Benoit
2012-02-04 12:16 ` [RFC PATCH 5/8] misc: emif: handle frequency and voltage change events Aneesh V
2012-02-16 10:38 ` Santosh Shilimkar
2012-02-16 11:22 ` Aneesh V
2012-02-04 12:16 ` [RFC PATCH 6/8] misc: emif: add interrupt and temperature handling Aneesh V
2012-02-16 10:41 ` Santosh Shilimkar
2012-02-16 11:50 ` Aneesh V
2012-02-04 12:16 ` [RFC PATCH 7/8] misc: emif: add one-time settings Aneesh V
2012-02-16 10:44 ` Santosh Shilimkar
2012-02-16 11:56 ` Aneesh V
2012-02-04 12:16 ` [RFC PATCH 8/8] misc: emif: add debugfs entries for emif Aneesh V
2012-02-16 10:46 ` Santosh Shilimkar
2012-02-16 10:51 ` Santosh Shilimkar [this message]
2012-02-16 16:23 ` [RFC PATCH 0/8] Add TI EMIF SDRAM controller driver Greg KH
2012-02-17 13:56 ` Aneesh V
2012-02-17 17:50 ` Greg KH
2012-02-20 14:07 ` Aneesh V
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